Obesity has been on the rise year after year due to factors such as the consumption of a high-fat diet resulting from the westernization of dietary habits, lack of daily exercise, and overeating as a result of excessive stress. Obesity causes the accumulation of large quantities of lipids in the liver, which leads to lifestyle-related diseases such as diabetes, hypertension, hyperlipidemia, heart disease, and cerebral hemorrhage. Therefore, the prevention of obesity is an extremely important factor in the prevention of lifestyle-related diseases. In particular, as we now prepare for an aged society, increases in lifestyle-related diseases have become problematic, and means for preventing obesity have also attracted attention from the perspective of preventive medicine. Searches for substances involved in the prevention of obesity from various food products and research on the action of these substances are therefore under way, and mannooligosaccharides have been the focus of attention from among these substances.
Japanese Unexamined Patent Application Publication 2006-169256 discloses the fact that mannooligosaccharides have a serum lipid improving action. Japanese Unexamined Patent Application Publication 2008-022778 discloses the fact that mannooligosaccharides have a diabetes preventing action. Further, Japanese Unexamined Patent Application Publication 2006-083127 discloses the fact that mannooligosaccharides have effects that prevent lifestyle-related diseases caused by obesity such as a body lipid reducing action. The Japan Journal of Food Engineering (6(4), 301-304 (2005)) has reported that mannooligosaccharides have an action which inhibits the absorption of ingested lipids, and the Journal of Medicine and Pharmaceutical Science (54(4), 505-509 (2005)) has reported that mannooligosaccharides have an action which reduces liver lipids.
However, it was previously unknown that the degrees of these actions greatly fluctuate due to changes in the degree of polymerization of mannooligosaccharides.